Simon - Mirror.co.uk

Simon Cowell yesterday branded Cheryl Cole "mad" and "vain" and claimed her acts would be better off if HE was in charge of them.

In yet another stinging attack on his fellow judge, the X Factor boss said Cheryl doesn't bring out the best in her acts.

Talking about Cher, Simon revealed: "When she gets criticised by me it's like she has been shot, and she is genuinely devastated and upset for 24 hours. Everyone thinks she looks up to Cheryl - but she looks up to me.

"Cheryl sees something of herself in Cher - it's vanity! Some might even say narcissism!" Simon says Cheryl was playing it too safe with Cher last week by putting her on a staircase, dressed in a nightie, and getting her to sing the John Lennon ballad Imagine. It could "ruin her chances of making the final", he said.

"You have got to take a risk with this girl. You have to trust she has enough young fans who would vote for her. Don't do a traditional safe X Factor song - do something that's her, because if she fakes it, she'll be out."

He says Cheryl isn't a good mentor to Rebecca, adding: "Rebecca's not a whimpering puppy. She's got steel in her. She genuinely wants to win. She argues passionately about the songs and the way she wants to do them. If her personality isn't coming across, it's Cheryl's fault. It's Cheryl's job. Or maybe Rebecca switches to me for a week, I'll get her personality out!" On Cheryl's third act, Katie, he said: "I think it's girls who dislike her, not guys. Like in schools, for some reason people turn against one person if they annoy them. I think whatever happens with our Katie she will have a career."

He said he liked Katie's drastic new haircut. "She was like, 'I'll cut off maybe you'll like this person.' I thought it was ballsy."

Simon claimed that Cheryl had copied the trademark military salute she has given fans throughout this series from him.

He says: "I did it on American Idol and it just demonstrates exactly what I thought was true. That before she came on the show she would spend hours and hours looking at me on the internet. She has now taken it and copied it. I'm going to find the footage and prove she is copying it. And I want it back!" Last night - at the beginning X of the show - smirking Cowell grabbed Cheryl's hand to stop her saluting... before doing it himself.

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Simon also accuses Cheryl of being "mad".

"The slogan this year was 'embrace the madness'. Cheryl says she can't work out if she is embracing it or actually going mad. It's a fine line - but Cheryl has always been mad! If you look into Cheryl's eyes you will see total madness! She was always fighting it but it was always there ready to come out. I've had the most bonkers conversations with Cheryl."

Simon's comments will stun Cheryl, who has said she is "sick and tired" of this year's show. And they will further increase speculation that their previously close relationship has come apart.

After Cheryl, 27, joined the show three years ago she became Simon's closest ally and the pair have often spoken of their fondness for each other. But that friendship seems to have soured lately. A fortnight ago Simon, 51, called her "a brat" and now he is questioning her ability as a mentor.

Rubbing more salt in the wound, he even talks about his admiration for Cheryl's rival judge Dannii. "If I had to choose a mentor other than myself, if I was a contestant, I'd want to be mentored by Dannii," he said.

But Louis Walsh gets both barrels from Simon too. "Louis doesn't listen to his tracks, doesn't care, hasn't got a clue and all he does is tell them to cry," said Simon. "That's his idea of mentoring. Unfortunately, it's working."

He also mocked Louis' hair, saying: "His hair has gone purple - lavender actually. He calls that maintenance. No, Louis... you have purple hair. Who's that woman who used to be in Coronation Street? Violet - he's turned into Violet Carson! (actress who played Ena Sharples) The hair. The look. Even the personality."

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